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avidec.c
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1 /*
2  * AVI demuxer
3  * Copyright (c) 2001 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/mathematics.h"
24 #include "libavutil/bswap.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/avstring.h"
28 #include "libavutil/avassert.h"
29 #include "avformat.h"
30 #include "internal.h"
31 #include "avi.h"
32 #include "dv.h"
33 #include "riff.h"
34 
35 typedef struct AVIStream {
36  int64_t frame_offset; /* current frame (video) or byte (audio) counter
37  (used to compute the pts) */
38  int remaining;
40 
41  uint32_t scale;
42  uint32_t rate;
43  int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */
44 
45  int64_t cum_len; /* temporary storage (used during seek) */
46 
47  int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
49  uint32_t pal[256];
50  int has_pal;
51  int dshow_block_align; ///< block align variable used to emulate bugs in the MS dshow demuxer
52 
56 
57  int64_t seek_pos;
58 } AVIStream;
59 
60 typedef struct {
61  const AVClass *class;
62  int64_t riff_end;
63  int64_t movi_end;
64  int64_t fsize;
65  int64_t io_fsize;
66  int64_t movi_list;
67  int64_t last_pkt_pos;
69  int is_odml;
74  int use_odml;
75 #define MAX_ODML_DEPTH 1000
76  int64_t dts_max;
77 } AVIContext;
78 
79 
80 static const AVOption options[] = {
81  { "use_odml", "use odml index", offsetof(AVIContext, use_odml), AV_OPT_TYPE_INT, {.i64 = 1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM},
82  { NULL },
83 };
84 
85 static const AVClass demuxer_class = {
86  .class_name = "avi",
87  .item_name = av_default_item_name,
88  .option = options,
89  .version = LIBAVUTIL_VERSION_INT,
90  .category = AV_CLASS_CATEGORY_DEMUXER,
91 };
92 
93 
94 static const char avi_headers[][8] = {
95  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', ' ' },
96  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 'X' },
97  { 'R', 'I', 'F', 'F', 'A', 'V', 'I', 0x19},
98  { 'O', 'N', '2', ' ', 'O', 'N', '2', 'f' },
99  { 'R', 'I', 'F', 'F', 'A', 'M', 'V', ' ' },
100  { 0 }
101 };
102 
104  { "strn", "title" },
105  { 0 },
106 };
107 
108 static int avi_load_index(AVFormatContext *s);
109 static int guess_ni_flag(AVFormatContext *s);
110 
111 #define print_tag(str, tag, size) \
112  av_dlog(NULL, "%s: tag=%c%c%c%c size=0x%x\n", \
113  str, tag & 0xff, \
114  (tag >> 8) & 0xff, \
115  (tag >> 16) & 0xff, \
116  (tag >> 24) & 0xff, \
117  size)
118 
119 static inline int get_duration(AVIStream *ast, int len){
120  if(ast->sample_size){
121  return len;
122  }else if (ast->dshow_block_align){
123  return (len + ast->dshow_block_align - 1)/ast->dshow_block_align;
124  }else
125  return 1;
126 }
127 
129 {
130  AVIContext *avi = s->priv_data;
131  char header[8];
132  int i;
133 
134  /* check RIFF header */
135  avio_read(pb, header, 4);
136  avi->riff_end = avio_rl32(pb); /* RIFF chunk size */
137  avi->riff_end += avio_tell(pb); /* RIFF chunk end */
138  avio_read(pb, header+4, 4);
139 
140  for(i=0; avi_headers[i][0]; i++)
141  if(!memcmp(header, avi_headers[i], 8))
142  break;
143  if(!avi_headers[i][0])
144  return AVERROR_INVALIDDATA;
145 
146  if(header[7] == 0x19)
147  av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");
148 
149  return 0;
150 }
151 
152 static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){
153  AVIContext *avi = s->priv_data;
154  AVIOContext *pb = s->pb;
155  int longs_pre_entry= avio_rl16(pb);
156  int index_sub_type = avio_r8(pb);
157  int index_type = avio_r8(pb);
158  int entries_in_use = avio_rl32(pb);
159  int chunk_id = avio_rl32(pb);
160  int64_t base = avio_rl64(pb);
161  int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');
162  AVStream *st;
163  AVIStream *ast;
164  int i;
165  int64_t last_pos= -1;
166  int64_t filesize= avi->fsize;
167 
168  av_dlog(s, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",
169  longs_pre_entry,index_type, entries_in_use, chunk_id, base);
170 
171  if(stream_id >= s->nb_streams || stream_id < 0)
172  return AVERROR_INVALIDDATA;
173  st= s->streams[stream_id];
174  ast = st->priv_data;
175 
176  if(index_sub_type)
177  return AVERROR_INVALIDDATA;
178 
179  avio_rl32(pb);
180 
181  if(index_type && longs_pre_entry != 2)
182  return AVERROR_INVALIDDATA;
183  if(index_type>1)
184  return AVERROR_INVALIDDATA;
185 
186  if(filesize > 0 && base >= filesize){
187  av_log(s, AV_LOG_ERROR, "ODML index invalid\n");
188  if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)
189  base &= 0xFFFFFFFF;
190  else
191  return AVERROR_INVALIDDATA;
192  }
193 
194  for(i=0; i<entries_in_use; i++){
195  if(index_type){
196  int64_t pos= avio_rl32(pb) + base - 8;
197  int len = avio_rl32(pb);
198  int key= len >= 0;
199  len &= 0x7FFFFFFF;
200 
201 #ifdef DEBUG_SEEK
202  av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);
203 #endif
204  if(url_feof(pb))
205  return AVERROR_INVALIDDATA;
206 
207  if(last_pos == pos || pos == base - 8)
208  avi->non_interleaved= 1;
209  if(last_pos != pos && (len || !ast->sample_size))
210  av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);
211 
212  ast->cum_len += get_duration(ast, len);
213  last_pos= pos;
214  }else{
215  int64_t offset, pos;
216  int duration;
217  offset = avio_rl64(pb);
218  avio_rl32(pb); /* size */
219  duration = avio_rl32(pb);
220 
221  if(url_feof(pb))
222  return AVERROR_INVALIDDATA;
223 
224  pos = avio_tell(pb);
225 
226  if(avi->odml_depth > MAX_ODML_DEPTH){
227  av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");
228  return AVERROR_INVALIDDATA;
229  }
230 
231  if(avio_seek(pb, offset+8, SEEK_SET) < 0)
232  return -1;
233  avi->odml_depth++;
234  read_braindead_odml_indx(s, frame_num);
235  avi->odml_depth--;
236  frame_num += duration;
237 
238  if(avio_seek(pb, pos, SEEK_SET) < 0) {
239  av_log(s, AV_LOG_ERROR, "Failed to restore position after reading index\n");
240  return -1;
241  }
242 
243  }
244  }
245  avi->index_loaded=2;
246  return 0;
247 }
248 
250  int i;
251  int64_t j;
252 
253  for(i=0; i<s->nb_streams; i++){
254  AVStream *st = s->streams[i];
255  AVIStream *ast = st->priv_data;
256  int n= st->nb_index_entries;
257  int max= ast->sample_size;
258  int64_t pos, size, ts;
259 
260  if(n != 1 || ast->sample_size==0)
261  continue;
262 
263  while(max < 1024) max+=max;
264 
265  pos= st->index_entries[0].pos;
266  size= st->index_entries[0].size;
267  ts= st->index_entries[0].timestamp;
268 
269  for(j=0; j<size; j+=max){
270  av_add_index_entry(st, pos+j, ts+j, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);
271  }
272  }
273 }
274 
275 static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag, uint32_t size)
276 {
277  AVIOContext *pb = s->pb;
278  char key[5] = {0}, *value;
279 
280  size += (size & 1);
281 
282  if (size == UINT_MAX)
283  return AVERROR(EINVAL);
284  value = av_malloc(size+1);
285  if (!value)
286  return AVERROR(ENOMEM);
287  avio_read(pb, value, size);
288  value[size]=0;
289 
290  AV_WL32(key, tag);
291 
292  return av_dict_set(st ? &st->metadata : &s->metadata, key, value,
294 }
295 
296 static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
297  "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
298 
299 static void avi_metadata_creation_time(AVDictionary **metadata, char *date)
300 {
301  char month[4], time[9], buffer[64];
302  int i, day, year;
303  /* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */
304  if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",
305  month, &day, time, &year) == 4) {
306  for (i=0; i<12; i++)
307  if (!av_strcasecmp(month, months[i])) {
308  snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",
309  year, i+1, day, time);
310  av_dict_set(metadata, "creation_time", buffer, 0);
311  }
312  } else if (date[4] == '/' && date[7] == '/') {
313  date[4] = date[7] = '-';
314  av_dict_set(metadata, "creation_time", date, 0);
315  }
316 }
317 
318 static void avi_read_nikon(AVFormatContext *s, uint64_t end)
319 {
320  while (avio_tell(s->pb) < end) {
321  uint32_t tag = avio_rl32(s->pb);
322  uint32_t size = avio_rl32(s->pb);
323  switch (tag) {
324  case MKTAG('n', 'c', 't', 'g'): { /* Nikon Tags */
325  uint64_t tag_end = avio_tell(s->pb) + size;
326  while (avio_tell(s->pb) < tag_end) {
327  uint16_t tag = avio_rl16(s->pb);
328  uint16_t size = avio_rl16(s->pb);
329  const char *name = NULL;
330  char buffer[64] = {0};
331  size -= avio_read(s->pb, buffer,
332  FFMIN(size, sizeof(buffer)-1));
333  switch (tag) {
334  case 0x03: name = "maker"; break;
335  case 0x04: name = "model"; break;
336  case 0x13: name = "creation_time";
337  if (buffer[4] == ':' && buffer[7] == ':')
338  buffer[4] = buffer[7] = '-';
339  break;
340  }
341  if (name)
342  av_dict_set(&s->metadata, name, buffer, 0);
343  avio_skip(s->pb, size);
344  }
345  break;
346  }
347  default:
348  avio_skip(s->pb, size);
349  break;
350  }
351  }
352 }
353 
355 {
356  AVIContext *avi = s->priv_data;
357  AVIOContext *pb = s->pb;
358  unsigned int tag, tag1, handler;
359  int codec_type, stream_index, frame_period;
360  unsigned int size;
361  int i;
362  AVStream *st;
363  AVIStream *ast = NULL;
364  int avih_width=0, avih_height=0;
365  int amv_file_format=0;
366  uint64_t list_end = 0;
367  int ret;
368  AVDictionaryEntry *dict_entry;
369 
370  avi->stream_index= -1;
371 
372  ret = get_riff(s, pb);
373  if (ret < 0)
374  return ret;
375 
376  av_log(avi, AV_LOG_DEBUG, "use odml:%d\n", avi->use_odml);
377 
378  avi->io_fsize = avi->fsize = avio_size(pb);
379  if(avi->fsize<=0 || avi->fsize < avi->riff_end)
380  avi->fsize= avi->riff_end == 8 ? INT64_MAX : avi->riff_end;
381 
382  /* first list tag */
383  stream_index = -1;
384  codec_type = -1;
385  frame_period = 0;
386  for(;;) {
387  if (url_feof(pb))
388  goto fail;
389  tag = avio_rl32(pb);
390  size = avio_rl32(pb);
391 
392  print_tag("tag", tag, size);
393 
394  switch(tag) {
395  case MKTAG('L', 'I', 'S', 'T'):
396  list_end = avio_tell(pb) + size;
397  /* Ignored, except at start of video packets. */
398  tag1 = avio_rl32(pb);
399 
400  print_tag("list", tag1, 0);
401 
402  if (tag1 == MKTAG('m', 'o', 'v', 'i')) {
403  avi->movi_list = avio_tell(pb) - 4;
404  if(size) avi->movi_end = avi->movi_list + size + (size & 1);
405  else avi->movi_end = avi->fsize;
406  av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);
407  goto end_of_header;
408  }
409  else if (tag1 == MKTAG('I', 'N', 'F', 'O'))
410  ff_read_riff_info(s, size - 4);
411  else if (tag1 == MKTAG('n', 'c', 'd', 't'))
412  avi_read_nikon(s, list_end);
413 
414  break;
415  case MKTAG('I', 'D', 'I', 'T'): {
416  unsigned char date[64] = {0};
417  size += (size & 1);
418  size -= avio_read(pb, date, FFMIN(size, sizeof(date)-1));
419  avio_skip(pb, size);
421  break;
422  }
423  case MKTAG('d', 'm', 'l', 'h'):
424  avi->is_odml = 1;
425  avio_skip(pb, size + (size & 1));
426  break;
427  case MKTAG('a', 'm', 'v', 'h'):
428  amv_file_format=1;
429  case MKTAG('a', 'v', 'i', 'h'):
430  /* AVI header */
431  /* using frame_period is bad idea */
432  frame_period = avio_rl32(pb);
433  avio_rl32(pb); /* max. bytes per second */
434  avio_rl32(pb);
436 
437  avio_skip(pb, 2 * 4);
438  avio_rl32(pb);
439  avio_rl32(pb);
440  avih_width=avio_rl32(pb);
441  avih_height=avio_rl32(pb);
442 
443  avio_skip(pb, size - 10 * 4);
444  break;
445  case MKTAG('s', 't', 'r', 'h'):
446  /* stream header */
447 
448  tag1 = avio_rl32(pb);
449  handler = avio_rl32(pb); /* codec tag */
450 
451  if(tag1 == MKTAG('p', 'a', 'd', 's')){
452  avio_skip(pb, size - 8);
453  break;
454  }else{
455  stream_index++;
456  st = avformat_new_stream(s, NULL);
457  if (!st)
458  goto fail;
459 
460  st->id = stream_index;
461  ast = av_mallocz(sizeof(AVIStream));
462  if (!ast)
463  goto fail;
464  st->priv_data = ast;
465  }
466  if(amv_file_format)
467  tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');
468 
469  print_tag("strh", tag1, -1);
470 
471  if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){
472  int64_t dv_dur;
473 
474  /*
475  * After some consideration -- I don't think we
476  * have to support anything but DV in type1 AVIs.
477  */
478  if (s->nb_streams != 1)
479  goto fail;
480 
481  if (handler != MKTAG('d', 'v', 's', 'd') &&
482  handler != MKTAG('d', 'v', 'h', 'd') &&
483  handler != MKTAG('d', 'v', 's', 'l'))
484  goto fail;
485 
486  ast = s->streams[0]->priv_data;
487  av_freep(&s->streams[0]->codec->extradata);
488  av_freep(&s->streams[0]->codec);
489  if (s->streams[0]->info)
491  av_freep(&s->streams[0]->info);
492  av_freep(&s->streams[0]);
493  s->nb_streams = 0;
494  if (CONFIG_DV_DEMUXER) {
495  avi->dv_demux = avpriv_dv_init_demux(s);
496  if (!avi->dv_demux)
497  goto fail;
498  }
499  s->streams[0]->priv_data = ast;
500  avio_skip(pb, 3 * 4);
501  ast->scale = avio_rl32(pb);
502  ast->rate = avio_rl32(pb);
503  avio_skip(pb, 4); /* start time */
504 
505  dv_dur = avio_rl32(pb);
506  if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {
507  dv_dur *= AV_TIME_BASE;
508  s->duration = av_rescale(dv_dur, ast->scale, ast->rate);
509  }
510  /*
511  * else, leave duration alone; timing estimation in utils.c
512  * will make a guess based on bitrate.
513  */
514 
515  stream_index = s->nb_streams - 1;
516  avio_skip(pb, size - 9*4);
517  break;
518  }
519 
520  av_assert0(stream_index < s->nb_streams);
521  st->codec->stream_codec_tag= handler;
522 
523  avio_rl32(pb); /* flags */
524  avio_rl16(pb); /* priority */
525  avio_rl16(pb); /* language */
526  avio_rl32(pb); /* initial frame */
527  ast->scale = avio_rl32(pb);
528  ast->rate = avio_rl32(pb);
529  if(!(ast->scale && ast->rate)){
530  av_log(s, AV_LOG_WARNING, "scale/rate is %u/%u which is invalid. (This file has been generated by broken software.)\n", ast->scale, ast->rate);
531  if(frame_period){
532  ast->rate = 1000000;
533  ast->scale = frame_period;
534  }else{
535  ast->rate = 25;
536  ast->scale = 1;
537  }
538  }
539  avpriv_set_pts_info(st, 64, ast->scale, ast->rate);
540 
541  ast->cum_len=avio_rl32(pb); /* start */
542  st->nb_frames = avio_rl32(pb);
543 
544  st->start_time = 0;
545  avio_rl32(pb); /* buffer size */
546  avio_rl32(pb); /* quality */
547  if (ast->cum_len*ast->scale/ast->rate > 3600) {
548  av_log(s, AV_LOG_ERROR, "crazy start time, iam scared, giving up\n");
549  return AVERROR_INVALIDDATA;
550  }
551  ast->sample_size = avio_rl32(pb); /* sample ssize */
552  ast->cum_len *= FFMAX(1, ast->sample_size);
553  av_dlog(s, "%"PRIu32" %"PRIu32" %d\n",
554  ast->rate, ast->scale, ast->sample_size);
555 
556  switch(tag1) {
557  case MKTAG('v', 'i', 'd', 's'):
558  codec_type = AVMEDIA_TYPE_VIDEO;
559 
560  ast->sample_size = 0;
561  break;
562  case MKTAG('a', 'u', 'd', 's'):
563  codec_type = AVMEDIA_TYPE_AUDIO;
564  break;
565  case MKTAG('t', 'x', 't', 's'):
566  codec_type = AVMEDIA_TYPE_SUBTITLE;
567  break;
568  case MKTAG('d', 'a', 't', 's'):
569  codec_type = AVMEDIA_TYPE_DATA;
570  break;
571  default:
572  av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);
573  }
574  if(ast->sample_size == 0) {
575  st->duration = st->nb_frames;
576  if (st->duration > 0 && avi->io_fsize > 0 && avi->riff_end > avi->io_fsize) {
577  av_log(s, AV_LOG_DEBUG, "File is truncated adjusting duration\n");
578  st->duration = av_rescale(st->duration, avi->io_fsize, avi->riff_end);
579  }
580  }
581  ast->frame_offset= ast->cum_len;
582  avio_skip(pb, size - 12 * 4);
583  break;
584  case MKTAG('s', 't', 'r', 'f'):
585  /* stream header */
586  if (!size)
587  break;
588  if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {
589  avio_skip(pb, size);
590  } else {
591  uint64_t cur_pos = avio_tell(pb);
592  unsigned esize;
593  if (cur_pos < list_end)
594  size = FFMIN(size, list_end - cur_pos);
595  st = s->streams[stream_index];
596  switch(codec_type) {
597  case AVMEDIA_TYPE_VIDEO:
598  if(amv_file_format){
599  st->codec->width=avih_width;
600  st->codec->height=avih_height;
603  avio_skip(pb, size);
604  break;
605  }
606  tag1 = ff_get_bmp_header(pb, st, &esize);
607 
608  if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {
610  st->codec->codec_tag = tag1;
612  break;
613  }
614 
615  if(size > 10*4 && size<(1<<30) && size < avi->fsize){
616  if(esize == size-1 && (esize&1)) st->codec->extradata_size= esize - 10*4;
617  else st->codec->extradata_size= size - 10*4;
619  if (!st->codec->extradata) {
620  st->codec->extradata_size= 0;
621  return AVERROR(ENOMEM);
622  }
623  avio_read(pb, st->codec->extradata, st->codec->extradata_size);
624  }
625 
626  if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
627  avio_r8(pb);
628 
629  /* Extract palette from extradata if bpp <= 8. */
630  /* This code assumes that extradata contains only palette. */
631  /* This is true for all paletted codecs implemented in FFmpeg. */
632  if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {
633  int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;
634  const uint8_t *pal_src;
635 
636  pal_size = FFMIN(pal_size, st->codec->extradata_size);
637  pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;
638  for (i = 0; i < pal_size/4; i++)
639  ast->pal[i] = 0xFFU<<24 | AV_RL32(pal_src+4*i);
640  ast->has_pal = 1;
641  }
642 
643  print_tag("video", tag1, 0);
644 
646  st->codec->codec_tag = tag1;
648  st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.
649 
650  if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){
651  st->codec->extradata_size+= 9;
653  if(st->codec->extradata)
654  memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);
655  }
656  st->codec->height= FFABS(st->codec->height);
657 
658 // avio_skip(pb, size - 5 * 4);
659  break;
660  case AVMEDIA_TYPE_AUDIO:
661  ret = ff_get_wav_header(pb, st->codec, size);
662  if (ret < 0)
663  return ret;
665  if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){
666  av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);
667  ast->sample_size= st->codec->block_align;
668  }
669  if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */
670  avio_skip(pb, 1);
671  /* Force parsing as several audio frames can be in
672  * one packet and timestamps refer to packet start. */
674  /* ADTS header is in extradata, AAC without header must be
675  * stored as exact frames. Parser not needed and it will
676  * fail. */
677  if (st->codec->codec_id == AV_CODEC_ID_AAC && st->codec->extradata_size)
679  /* AVI files with Xan DPCM audio (wrongly) declare PCM
680  * audio in the header but have Axan as stream_code_tag. */
681  if (st->codec->stream_codec_tag == AV_RL32("Axan")){
683  st->codec->codec_tag = 0;
684  ast->dshow_block_align = 0;
685  }
686  if (amv_file_format){
688  ast->dshow_block_align = 0;
689  }
690  if(st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align <= 4 && ast->dshow_block_align) {
691  av_log(s, AV_LOG_DEBUG, "overriding invalid dshow_block_align of %d\n", ast->dshow_block_align);
692  ast->dshow_block_align = 0;
693  }
694  if(st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 1024 && ast->sample_size == 1024 ||
695  st->codec->codec_id == AV_CODEC_ID_AAC && ast->dshow_block_align == 4096 && ast->sample_size == 4096 ||
696  st->codec->codec_id == AV_CODEC_ID_MP3 && ast->dshow_block_align == 1152 && ast->sample_size == 1152) {
697  av_log(s, AV_LOG_DEBUG, "overriding sample_size\n");
698  ast->sample_size = 0;
699  }
700  break;
703  st->request_probe= 1;
704  avio_skip(pb, size);
705  break;
706  default:
709  st->codec->codec_tag= 0;
710  avio_skip(pb, size);
711  break;
712  }
713  }
714  break;
715  case MKTAG('s', 't', 'r', 'd'):
716  if (stream_index >= (unsigned)s->nb_streams
717  || s->streams[stream_index]->codec->extradata_size
718  || s->streams[stream_index]->codec->codec_tag == MKTAG('H','2','6','4')) {
719  avio_skip(pb, size);
720  } else {
721  uint64_t cur_pos = avio_tell(pb);
722  if (cur_pos < list_end)
723  size = FFMIN(size, list_end - cur_pos);
724  st = s->streams[stream_index];
725 
726  if(size<(1<<30)){
727  st->codec->extradata_size= size;
729  if (!st->codec->extradata) {
730  st->codec->extradata_size= 0;
731  return AVERROR(ENOMEM);
732  }
733  avio_read(pb, st->codec->extradata, st->codec->extradata_size);
734  }
735 
736  if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly
737  avio_r8(pb);
738  }
739  break;
740  case MKTAG('i', 'n', 'd', 'x'):
741  i= avio_tell(pb);
742  if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) && avi->use_odml &&
744  goto fail;
745  avio_seek(pb, i+size, SEEK_SET);
746  break;
747  case MKTAG('v', 'p', 'r', 'p'):
748  if(stream_index < (unsigned)s->nb_streams && size > 9*4){
749  AVRational active, active_aspect;
750 
751  st = s->streams[stream_index];
752  avio_rl32(pb);
753  avio_rl32(pb);
754  avio_rl32(pb);
755  avio_rl32(pb);
756  avio_rl32(pb);
757 
758  active_aspect.den= avio_rl16(pb);
759  active_aspect.num= avio_rl16(pb);
760  active.num = avio_rl32(pb);
761  active.den = avio_rl32(pb);
762  avio_rl32(pb); //nbFieldsPerFrame
763 
764  if(active_aspect.num && active_aspect.den && active.num && active.den){
765  st->sample_aspect_ratio= av_div_q(active_aspect, active);
766  av_dlog(s, "vprp %d/%d %d/%d\n",
767  active_aspect.num, active_aspect.den,
768  active.num, active.den);
769  }
770  size -= 9*4;
771  }
772  avio_skip(pb, size);
773  break;
774  case MKTAG('s', 't', 'r', 'n'):
775  if(s->nb_streams){
776  ret = avi_read_tag(s, s->streams[s->nb_streams-1], tag, size);
777  if (ret < 0)
778  return ret;
779  break;
780  }
781  default:
782  if(size > 1000000){
783  av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "
784  "I will ignore it and try to continue anyway.\n");
786  goto fail;
787  avi->movi_list = avio_tell(pb) - 4;
788  avi->movi_end = avi->fsize;
789  goto end_of_header;
790  }
791  /* skip tag */
792  size += (size & 1);
793  avio_skip(pb, size);
794  break;
795  }
796  }
797  end_of_header:
798  /* check stream number */
799  if (stream_index != s->nb_streams - 1) {
800  fail:
801  return AVERROR_INVALIDDATA;
802  }
803 
804  if(!avi->index_loaded && pb->seekable)
805  avi_load_index(s);
806  avi->index_loaded |= 1;
808 
809  dict_entry = av_dict_get(s->metadata, "ISFT", NULL, 0);
810  if (dict_entry && !strcmp(dict_entry->value, "PotEncoder"))
811  for (i=0; i<s->nb_streams; i++) {
812  AVStream *st = s->streams[i];
816  }
817 
818  for(i=0; i<s->nb_streams; i++){
819  AVStream *st = s->streams[i];
820  if(st->nb_index_entries)
821  break;
822  }
823  // DV-in-AVI cannot be non-interleaved, if set this must be
824  // a mis-detection.
825  if(avi->dv_demux)
826  avi->non_interleaved=0;
827  if(i==s->nb_streams && avi->non_interleaved) {
828  av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");
829  avi->non_interleaved=0;
830  }
831 
832  if(avi->non_interleaved) {
833  av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");
834  clean_index(s);
835  }
836 
837  ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);
839 
840  return 0;
841 }
842 
843 static int read_gab2_sub(AVStream *st, AVPacket *pkt) {
844  if (pkt->data && !strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data+5) == 2) {
845  uint8_t desc[256];
846  int score = AVPROBE_SCORE_EXTENSION, ret;
847  AVIStream *ast = st->priv_data;
848  AVInputFormat *sub_demuxer;
849  AVRational time_base;
850  AVIOContext *pb = avio_alloc_context( pkt->data + 7,
851  pkt->size - 7,
852  0, NULL, NULL, NULL, NULL);
853  AVProbeData pd;
854  unsigned int desc_len = avio_rl32(pb);
855 
856  if (desc_len > pb->buf_end - pb->buf_ptr)
857  goto error;
858 
859  ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));
860  avio_skip(pb, desc_len - ret);
861  if (*desc)
862  av_dict_set(&st->metadata, "title", desc, 0);
863 
864  avio_rl16(pb); /* flags? */
865  avio_rl32(pb); /* data size */
866 
867  pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };
868  if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))
869  goto error;
870 
871  if (!(ast->sub_ctx = avformat_alloc_context()))
872  goto error;
873 
874  ast->sub_ctx->pb = pb;
875  if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {
876  ff_read_packet(ast->sub_ctx, &ast->sub_pkt);
877  *st->codec = *ast->sub_ctx->streams[0]->codec;
878  ast->sub_ctx->streams[0]->codec->extradata = NULL;
879  time_base = ast->sub_ctx->streams[0]->time_base;
880  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
881  }
882  ast->sub_buffer = pkt->data;
883  memset(pkt, 0, sizeof(*pkt));
884  return 1;
885 error:
886  av_freep(&pb);
887  }
888  return 0;
889 }
890 
892  AVPacket *pkt)
893 {
894  AVIStream *ast, *next_ast = next_st->priv_data;
895  int64_t ts, next_ts, ts_min = INT64_MAX;
896  AVStream *st, *sub_st = NULL;
897  int i;
898 
899  next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,
901 
902  for (i=0; i<s->nb_streams; i++) {
903  st = s->streams[i];
904  ast = st->priv_data;
905  if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {
907  if (ts <= next_ts && ts < ts_min) {
908  ts_min = ts;
909  sub_st = st;
910  }
911  }
912  }
913 
914  if (sub_st) {
915  ast = sub_st->priv_data;
916  *pkt = ast->sub_pkt;
917  pkt->stream_index = sub_st->index;
918  if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)
919  ast->sub_pkt.data = NULL;
920  }
921  return sub_st;
922 }
923 
924 static int get_stream_idx(int *d){
925  if( d[0] >= '0' && d[0] <= '9'
926  && d[1] >= '0' && d[1] <= '9'){
927  return (d[0] - '0') * 10 + (d[1] - '0');
928  }else{
929  return 100; //invalid stream ID
930  }
931 }
932 
933 /**
934  *
935  * @param exit_early set to 1 to just gather packet position without making the changes needed to actually read & return the packet
936  */
937 static int avi_sync(AVFormatContext *s, int exit_early)
938 {
939  AVIContext *avi = s->priv_data;
940  AVIOContext *pb = s->pb;
941  int n;
942  unsigned int d[8];
943  unsigned int size;
944  int64_t i, sync;
945 
946 start_sync:
947  memset(d, -1, sizeof(d));
948  for(i=sync=avio_tell(pb); !url_feof(pb); i++) {
949  int j;
950 
951  for(j=0; j<7; j++)
952  d[j]= d[j+1];
953  d[7]= avio_r8(pb);
954 
955  size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);
956 
957  n= get_stream_idx(d+2);
958  av_dlog(s, "%X %X %X %X %X %X %X %X %"PRId64" %u %d\n",
959  d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);
960  if(i*(avi->io_fsize>0) + (uint64_t)size > avi->fsize || d[0] > 127)
961  continue;
962 
963  //parse ix##
964  if( (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)
965  //parse JUNK
966  ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')
967  ||(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')){
968  avio_skip(pb, size);
969  goto start_sync;
970  }
971 
972  //parse stray LIST
973  if(d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T'){
974  avio_skip(pb, 4);
975  goto start_sync;
976  }
977 
978  n= get_stream_idx(d);
979 
980  if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)
981  continue;
982 
983  //detect ##ix chunk and skip
984  if(d[2] == 'i' && d[3] == 'x' && n < s->nb_streams){
985  avio_skip(pb, size);
986  goto start_sync;
987  }
988 
989  //parse ##dc/##wb
990  if(n < s->nb_streams){
991  AVStream *st;
992  AVIStream *ast;
993  st = s->streams[n];
994  ast = st->priv_data;
995 
996  if (!ast) {
997  av_log(s, AV_LOG_WARNING, "Skiping foreign stream %d packet\n", n);
998  continue;
999  }
1000 
1001  if(s->nb_streams>=2){
1002  AVStream *st1 = s->streams[1];
1003  AVIStream *ast1= st1->priv_data;
1004  //workaround for broken small-file-bug402.avi
1005  if( d[2] == 'w' && d[3] == 'b'
1006  && n==0
1007  && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO
1008  && st1->codec->codec_type == AVMEDIA_TYPE_AUDIO
1009  && ast->prefix == 'd'*256+'c'
1010  && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)
1011  ){
1012  n=1;
1013  st = st1;
1014  ast = ast1;
1015  av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");
1016  }
1017  }
1018 
1019 
1020  if( (st->discard >= AVDISCARD_DEFAULT && size==0)
1021  /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & AV_PKT_FLAG_KEY))*/ //FIXME needs a little reordering
1022  || st->discard >= AVDISCARD_ALL){
1023  if (!exit_early) {
1024  ast->frame_offset += get_duration(ast, size);
1025  avio_skip(pb, size);
1026  goto start_sync;
1027  }
1028  }
1029 
1030  if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {
1031  int k = avio_r8(pb);
1032  int last = (k + avio_r8(pb) - 1) & 0xFF;
1033 
1034  avio_rl16(pb); //flags
1035 
1036  for (; k <= last; k++)
1037  ast->pal[k] = 0xFFU<<24 | avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);
1038  ast->has_pal= 1;
1039  goto start_sync;
1040  } else if( ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||
1041  d[2]*256+d[3] == ast->prefix /*||
1042  (d[2] == 'd' && d[3] == 'c') ||
1043  (d[2] == 'w' && d[3] == 'b')*/) {
1044 
1045  if (exit_early)
1046  return 0;
1047  if(d[2]*256+d[3] == ast->prefix)
1048  ast->prefix_count++;
1049  else{
1050  ast->prefix= d[2]*256+d[3];
1051  ast->prefix_count= 0;
1052  }
1053 
1054  avi->stream_index= n;
1055  ast->packet_size= size + 8;
1056  ast->remaining= size;
1057 
1058  if(size || !ast->sample_size){
1059  uint64_t pos= avio_tell(pb) - 8;
1060  if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){
1061  av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);
1062  }
1063  }
1064  return 0;
1065  }
1066  }
1067  }
1068 
1069  if(pb->error)
1070  return pb->error;
1071  return AVERROR_EOF;
1072 }
1073 
1075 {
1076  AVIContext *avi = s->priv_data;
1077  AVIOContext *pb = s->pb;
1078  int err;
1079 #if FF_API_DESTRUCT_PACKET
1080  void* dstr;
1081 #endif
1082 
1083  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1084  int size = avpriv_dv_get_packet(avi->dv_demux, pkt);
1085  if (size >= 0)
1086  return size;
1087  }
1088 
1089  if(avi->non_interleaved){
1090  int best_stream_index = 0;
1091  AVStream *best_st= NULL;
1092  AVIStream *best_ast;
1093  int64_t best_ts= INT64_MAX;
1094  int i;
1095 
1096  for(i=0; i<s->nb_streams; i++){
1097  AVStream *st = s->streams[i];
1098  AVIStream *ast = st->priv_data;
1099  int64_t ts= ast->frame_offset;
1100  int64_t last_ts;
1101 
1102  if(!st->nb_index_entries)
1103  continue;
1104 
1105  last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;
1106  if(!ast->remaining && ts > last_ts)
1107  continue;
1108 
1109  ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});
1110 
1111  av_dlog(s, "%"PRId64" %d/%d %"PRId64"\n", ts,
1112  st->time_base.num, st->time_base.den, ast->frame_offset);
1113  if(ts < best_ts){
1114  best_ts= ts;
1115  best_st= st;
1116  best_stream_index= i;
1117  }
1118  }
1119  if(!best_st)
1120  return AVERROR_EOF;
1121 
1122  best_ast = best_st->priv_data;
1123  best_ts = best_ast->frame_offset;
1124  if(best_ast->remaining)
1126  else{
1127  i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);
1128  if(i>=0)
1129  best_ast->frame_offset= best_st->index_entries[i].timestamp;
1130  }
1131 
1132  if(i>=0){
1133  int64_t pos= best_st->index_entries[i].pos;
1134  pos += best_ast->packet_size - best_ast->remaining;
1135  if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)
1136  return AVERROR_EOF;
1137 
1138  av_assert0(best_ast->remaining <= best_ast->packet_size);
1139 
1140  avi->stream_index= best_stream_index;
1141  if(!best_ast->remaining)
1142  best_ast->packet_size=
1143  best_ast->remaining= best_st->index_entries[i].size;
1144  }
1145  else
1146  return AVERROR_EOF;
1147  }
1148 
1149 resync:
1150  if(avi->stream_index >= 0){
1151  AVStream *st= s->streams[ avi->stream_index ];
1152  AVIStream *ast= st->priv_data;
1153  int size, err;
1154 
1155  if(get_subtitle_pkt(s, st, pkt))
1156  return 0;
1157 
1158  if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM
1159  size= INT_MAX;
1160  else if(ast->sample_size < 32)
1161  // arbitrary multiplier to avoid tiny packets for raw PCM data
1162  size= 1024*ast->sample_size;
1163  else
1164  size= ast->sample_size;
1165 
1166  if(size > ast->remaining)
1167  size= ast->remaining;
1168  avi->last_pkt_pos= avio_tell(pb);
1169  err= av_get_packet(pb, pkt, size);
1170  if(err<0)
1171  return err;
1172  size = err;
1173 
1174  if(ast->has_pal && pkt->size<(unsigned)INT_MAX/2){
1175  uint8_t *pal;
1177  if(!pal){
1178  av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");
1179  }else{
1180  memcpy(pal, ast->pal, AVPALETTE_SIZE);
1181  ast->has_pal = 0;
1182  }
1183  }
1184 
1185  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1186  AVBufferRef *avbuf = pkt->buf;
1187 #if FF_API_DESTRUCT_PACKET
1188  dstr = pkt->destruct;
1189 #endif
1190  size = avpriv_dv_produce_packet(avi->dv_demux, pkt,
1191  pkt->data, pkt->size, pkt->pos);
1192 #if FF_API_DESTRUCT_PACKET
1193  pkt->destruct = dstr;
1194 #endif
1195  pkt->buf = avbuf;
1197  if (size < 0)
1199  } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE
1200  && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {
1201  ast->frame_offset++;
1202  avi->stream_index = -1;
1203  ast->remaining = 0;
1204  goto resync;
1205  } else {
1206  /* XXX: How to handle B-frames in AVI? */
1207  pkt->dts = ast->frame_offset;
1208 // pkt->dts += ast->start;
1209  if(ast->sample_size)
1210  pkt->dts /= ast->sample_size;
1211  av_dlog(s, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n",
1212  pkt->dts, ast->frame_offset, ast->scale, ast->rate,
1213  ast->sample_size, AV_TIME_BASE, avi->stream_index, size);
1214  pkt->stream_index = avi->stream_index;
1215 
1216  if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
1217  AVIndexEntry *e;
1218  int index;
1220 
1221  index= av_index_search_timestamp(st, ast->frame_offset, 0);
1222  e= &st->index_entries[index];
1223 
1224  if(index >= 0 && e->timestamp == ast->frame_offset){
1225  if (index == st->nb_index_entries-1){
1226  int key=1;
1227  int i;
1228  uint32_t state=-1;
1229  for(i=0; i<FFMIN(size,256); i++){
1230  if(st->codec->codec_id == AV_CODEC_ID_MPEG4){
1231  if(state == 0x1B6){
1232  key= !(pkt->data[i]&0xC0);
1233  break;
1234  }
1235  }else
1236  break;
1237  state= (state<<8) + pkt->data[i];
1238  }
1239  if(!key)
1240  e->flags &= ~AVINDEX_KEYFRAME;
1241  }
1242  if (e->flags & AVINDEX_KEYFRAME)
1244  }
1245  } else {
1247  }
1248  ast->frame_offset += get_duration(ast, pkt->size);
1249  }
1250  ast->remaining -= err;
1251  if(!ast->remaining){
1252  avi->stream_index= -1;
1253  ast->packet_size= 0;
1254  }
1255 
1256  if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){
1258  goto resync;
1259  }
1260  ast->seek_pos= 0;
1261 
1262  if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){
1263  int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);
1264 
1265  if(avi->dts_max - dts > 2*AV_TIME_BASE){
1266  avi->non_interleaved= 1;
1267  av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");
1268  }else if(avi->dts_max < dts)
1269  avi->dts_max = dts;
1270  }
1271 
1272  return 0;
1273  }
1274 
1275  if ((err = avi_sync(s, 0)) < 0)
1276  return err;
1277  goto resync;
1278 }
1279 
1280 /* XXX: We make the implicit supposition that the positions are sorted
1281  for each stream. */
1282 static int avi_read_idx1(AVFormatContext *s, int size)
1283 {
1284  AVIContext *avi = s->priv_data;
1285  AVIOContext *pb = s->pb;
1286  int nb_index_entries, i;
1287  AVStream *st;
1288  AVIStream *ast;
1289  unsigned int index, tag, flags, pos, len, first_packet = 1;
1290  unsigned last_pos= -1;
1291  unsigned last_idx= -1;
1292  int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;
1293  int anykey = 0;
1294 
1295  nb_index_entries = size / 16;
1296  if (nb_index_entries <= 0)
1297  return AVERROR_INVALIDDATA;
1298 
1299  idx1_pos = avio_tell(pb);
1300  avio_seek(pb, avi->movi_list+4, SEEK_SET);
1301  if (avi_sync(s, 1) == 0) {
1302  first_packet_pos = avio_tell(pb) - 8;
1303  }
1304  avi->stream_index = -1;
1305  avio_seek(pb, idx1_pos, SEEK_SET);
1306 
1307  if (s->nb_streams == 1 && s->streams[0]->codec->codec_tag == AV_RL32("MMES")){
1308  first_packet_pos = 0;
1309  data_offset = avi->movi_list;
1310  }
1311 
1312  /* Read the entries and sort them in each stream component. */
1313  for(i = 0; i < nb_index_entries; i++) {
1314  if(url_feof(pb))
1315  return -1;
1316 
1317  tag = avio_rl32(pb);
1318  flags = avio_rl32(pb);
1319  pos = avio_rl32(pb);
1320  len = avio_rl32(pb);
1321  av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
1322  i, tag, flags, pos, len);
1323 
1324  index = ((tag & 0xff) - '0') * 10;
1325  index += ((tag >> 8) & 0xff) - '0';
1326  if (index >= s->nb_streams)
1327  continue;
1328  st = s->streams[index];
1329  ast = st->priv_data;
1330 
1331  if(first_packet && first_packet_pos && len) {
1332  data_offset = first_packet_pos - pos;
1333  first_packet = 0;
1334  }
1335  pos += data_offset;
1336 
1337  av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);
1338 
1339  // even if we have only a single stream, we should
1340  // switch to non-interleaved to get correct timestamps
1341  if(last_pos == pos)
1342  avi->non_interleaved= 1;
1343  if(last_idx != pos && len) {
1344  av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
1345  last_idx= pos;
1346  }
1347  ast->cum_len += get_duration(ast, len);
1348  last_pos= pos;
1349  anykey |= flags&AVIIF_INDEX;
1350  }
1351  if (!anykey) {
1352  for (index = 0; index < s->nb_streams; index++) {
1353  st = s->streams[index];
1354  if (st->nb_index_entries)
1356  }
1357  }
1358  return 0;
1359 }
1360 
1362  int i;
1363  int64_t last_start=0;
1364  int64_t first_end= INT64_MAX;
1365  int64_t oldpos= avio_tell(s->pb);
1366  int *idx;
1367  int64_t min_pos, pos;
1368 
1369  for(i=0; i<s->nb_streams; i++){
1370  AVStream *st = s->streams[i];
1371  int n= st->nb_index_entries;
1372  unsigned int size;
1373 
1374  if(n <= 0)
1375  continue;
1376 
1377  if(n >= 2){
1378  int64_t pos= st->index_entries[0].pos;
1379  avio_seek(s->pb, pos + 4, SEEK_SET);
1380  size= avio_rl32(s->pb);
1381  if(pos + size > st->index_entries[1].pos)
1382  last_start= INT64_MAX;
1383  }
1384 
1385  if(st->index_entries[0].pos > last_start)
1386  last_start= st->index_entries[0].pos;
1387  if(st->index_entries[n-1].pos < first_end)
1388  first_end= st->index_entries[n-1].pos;
1389  }
1390  avio_seek(s->pb, oldpos, SEEK_SET);
1391  if (last_start > first_end)
1392  return 1;
1393  idx= av_mallocz(sizeof(*idx) * s->nb_streams);
1394  for (min_pos=pos=0; min_pos!=INT64_MAX; pos= min_pos+1LU) {
1395  int64_t max_dts = INT64_MIN/2, min_dts= INT64_MAX/2;
1396  min_pos = INT64_MAX;
1397 
1398  for (i=0; i<s->nb_streams; i++) {
1399  AVStream *st = s->streams[i];
1400  AVIStream *ast = st->priv_data;
1401  int n= st->nb_index_entries;
1402  while (idx[i]<n && st->index_entries[idx[i]].pos < pos)
1403  idx[i]++;
1404  if (idx[i] < n) {
1405  min_dts = FFMIN(min_dts, av_rescale_q(st->index_entries[idx[i]].timestamp/FFMAX(ast->sample_size, 1), st->time_base, AV_TIME_BASE_Q));
1406  min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);
1407  }
1408  if (idx[i])
1409  max_dts = FFMAX(max_dts, av_rescale_q(st->index_entries[idx[i]-1].timestamp/FFMAX(ast->sample_size, 1), st->time_base, AV_TIME_BASE_Q));
1410  }
1411  if(max_dts - min_dts > 2*AV_TIME_BASE) {
1412  av_free(idx);
1413  return 1;
1414  }
1415  }
1416  av_free(idx);
1417  return 0;
1418 }
1419 
1421 {
1422  AVIContext *avi = s->priv_data;
1423  AVIOContext *pb = s->pb;
1424  uint32_t tag, size;
1425  int64_t pos= avio_tell(pb);
1426  int64_t next;
1427  int ret = -1;
1428 
1429  if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)
1430  goto the_end; // maybe truncated file
1431  av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);
1432  for(;;) {
1433  tag = avio_rl32(pb);
1434  size = avio_rl32(pb);
1435  if (url_feof(pb))
1436  break;
1437  next = avio_tell(pb) + size + (size & 1);
1438 
1439  av_dlog(s, "tag=%c%c%c%c size=0x%x\n",
1440  tag & 0xff,
1441  (tag >> 8) & 0xff,
1442  (tag >> 16) & 0xff,
1443  (tag >> 24) & 0xff,
1444  size);
1445 
1446  if (tag == MKTAG('i', 'd', 'x', '1') &&
1447  avi_read_idx1(s, size) >= 0) {
1448  avi->index_loaded=2;
1449  ret = 0;
1450  }else if(tag == MKTAG('L', 'I', 'S', 'T')) {
1451  uint32_t tag1 = avio_rl32(pb);
1452 
1453  if (tag1 == MKTAG('I', 'N', 'F', 'O'))
1454  ff_read_riff_info(s, size - 4);
1455  }else if(!ret)
1456  break;
1457 
1458  if (avio_seek(pb, next, SEEK_SET) < 0)
1459  break; // something is wrong here
1460  }
1461  the_end:
1462  avio_seek(pb, pos, SEEK_SET);
1463  return ret;
1464 }
1465 
1466 static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)
1467 {
1468  AVIStream *ast2 = st2->priv_data;
1469  int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);
1470  av_free_packet(&ast2->sub_pkt);
1471  if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||
1472  avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)
1473  ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);
1474 }
1475 
1476 static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
1477 {
1478  AVIContext *avi = s->priv_data;
1479  AVStream *st;
1480  int i, index;
1481  int64_t pos, pos_min;
1482  AVIStream *ast;
1483 
1484  if (!avi->index_loaded) {
1485  /* we only load the index on demand */
1486  avi_load_index(s);
1487  avi->index_loaded |= 1;
1488  }
1489  av_assert0(stream_index>= 0);
1490 
1491  st = s->streams[stream_index];
1492  ast= st->priv_data;
1493  index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);
1494  if (index<0) {
1495  if (st->nb_index_entries > 0)
1496  av_log(s, AV_LOG_DEBUG, "Failed to find timestamp %"PRId64 " in index %"PRId64 " .. %"PRId64 "\n",
1497  timestamp * FFMAX(ast->sample_size, 1),
1498  st->index_entries[0].timestamp,
1500  return AVERROR_INVALIDDATA;
1501  }
1502 
1503  /* find the position */
1504  pos = st->index_entries[index].pos;
1505  timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);
1506 
1507  av_dlog(s, "XX %"PRId64" %d %"PRId64"\n",
1508  timestamp, index, st->index_entries[index].timestamp);
1509 
1510  if (CONFIG_DV_DEMUXER && avi->dv_demux) {
1511  /* One and only one real stream for DV in AVI, and it has video */
1512  /* offsets. Calling with other stream indexes should have failed */
1513  /* the av_index_search_timestamp call above. */
1514  av_assert0(stream_index == 0);
1515 
1516  if(avio_seek(s->pb, pos, SEEK_SET) < 0)
1517  return -1;
1518 
1519  /* Feed the DV video stream version of the timestamp to the */
1520  /* DV demux so it can synthesize correct timestamps. */
1521  ff_dv_offset_reset(avi->dv_demux, timestamp);
1522 
1523  avi->stream_index= -1;
1524  return 0;
1525  }
1526 
1527  pos_min= pos;
1528  for(i = 0; i < s->nb_streams; i++) {
1529  AVStream *st2 = s->streams[i];
1530  AVIStream *ast2 = st2->priv_data;
1531 
1532  ast2->packet_size=
1533  ast2->remaining= 0;
1534 
1535  if (ast2->sub_ctx) {
1536  seek_subtitle(st, st2, timestamp);
1537  continue;
1538  }
1539 
1540  if (st2->nb_index_entries <= 0)
1541  continue;
1542 
1543 // av_assert1(st2->codec->block_align);
1544  av_assert0((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);
1545  index = av_index_search_timestamp(
1546  st2,
1547  av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1549  if(index<0)
1550  index=0;
1551  ast2->seek_pos= st2->index_entries[index].pos;
1552  pos_min= FFMIN(pos_min,ast2->seek_pos);
1553  }
1554  for(i = 0; i < s->nb_streams; i++) {
1555  AVStream *st2 = s->streams[i];
1556  AVIStream *ast2 = st2->priv_data;
1557 
1558  if (ast2->sub_ctx || st2->nb_index_entries <= 0)
1559  continue;
1560 
1561  index = av_index_search_timestamp(
1562  st2,
1563  av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),
1565  if(index<0)
1566  index=0;
1567  while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)
1568  index--;
1569  ast2->frame_offset = st2->index_entries[index].timestamp;
1570  }
1571 
1572  /* do the seek */
1573  if (avio_seek(s->pb, pos_min, SEEK_SET) < 0) {
1574  av_log(s, AV_LOG_ERROR, "Seek failed\n");
1575  return -1;
1576  }
1577  avi->stream_index= -1;
1578  avi->dts_max= INT_MIN;
1579  return 0;
1580 }
1581 
1583 {
1584  int i;
1585  AVIContext *avi = s->priv_data;
1586 
1587  for(i=0;i<s->nb_streams;i++) {
1588  AVStream *st = s->streams[i];
1589  AVIStream *ast = st->priv_data;
1590  if (ast) {
1591  if (ast->sub_ctx) {
1592  av_freep(&ast->sub_ctx->pb);
1594  }
1595  av_free(ast->sub_buffer);
1596  av_free_packet(&ast->sub_pkt);
1597  }
1598  }
1599 
1600  av_free(avi->dv_demux);
1601 
1602  return 0;
1603 }
1604 
1605 static int avi_probe(AVProbeData *p)
1606 {
1607  int i;
1608 
1609  /* check file header */
1610  for(i=0; avi_headers[i][0]; i++)
1611  if(!memcmp(p->buf , avi_headers[i] , 4) &&
1612  !memcmp(p->buf+8, avi_headers[i]+4, 4))
1613  return AVPROBE_SCORE_MAX;
1614 
1615  return 0;
1616 }
1617 
1619  .name = "avi",
1620  .long_name = NULL_IF_CONFIG_SMALL("AVI (Audio Video Interleaved)"),
1621  .priv_data_size = sizeof(AVIContext),
1622  .read_probe = avi_probe,
1627  .priv_class = &demuxer_class,
1628 };